Radiation sensitive apparatus for detecting conveyed articles

ABSTRACT

An improved article-detecting apparatus for use with a counting machine of the type having a conveyor for carrying articles to be counted from a supply hopper to a batching station, the detecting apparatus is adapted to sense each article on said conveyor and to provide a signal output for a counter in response to each article that is sensed, the detecting apparatus comprises a light source for directing a substantially horizontal beam of light laterally across the conveyor to a photocell, and means for vertically adjusting the light beam and photocell relative to the conveyor.

United States Patent [56] References Cited UNITED STATES PATENTS 5/1962Cubellis........................

[72] lnventor Michael C. Klapes Lynnfield, Mass. 21 AppLNo. 760,340

3,032,691 3,197,646 7/1965 Anders et al...... 3,207,909 9/1965 Lakso etal.

[22] Filed Sept. 17, 1968 [45] Patented Apr. 6, 1971 {73] Assignee DeltaEngineering Corporation Winchester, Mass.

[54] RADIATION SENSITIVE APPARATUS FUR DETECTING CONVEYEI) ARTICLESbatching station, the detecting apparatus is adapted to sense yor and toprovide a signal output sponse to each article that is sensed, thedetecting apparatus comprises a light source for directing asubstantially horizontal beam of light laterally across the conveyor toa photocell, and means for vertically adjusting the light beam andphotocell relative to the convey um a ms 2 2 72 5m 5 5 2, 2

m mm w m m m W W d C mm 7U IF 1 l] 2 1O 5 55 [I Menmd M 3 Sheets-Sheet lINVENTOR MICHAEL C. KLAPES ATTORNEY Patented Aprfifl fi WM 3Sheets-Sheet 2 INVENTOR MICHAEL C KLAPES ATTORNEY 3 Sheets-Sheet .3

INVENTOR MICHAEL C. K LAPES %Z; a aw? ATTORNEY litADllA'llIlUN SENSITIVEAIPIPALRATUfi FOR DETECTING CGNVEYIEID AIII'IICILTES This inventionrelates to machines for counting and batching articles at high speedsand more particularly to an improved article counting system.

Counting machines of the type to which this invention relates are wellknown in the art, e.g., US. Pat. No. Re. 25,01 3, issued Jul. 25, 1961,to EC. Cleveland et al. for Apparatus For Counting And lPackagingArticles, and my prior U.S. Pat. No. 3,001,636, issued Sept. 26, 1961,for Apparatus For Channeling Articles. These machines have wide utilityand are used, for example, in the drug and hardware industries tofacilitate filling of individual packets, boxes, and other containerswith a predetermined number of articles. Essentially, such machinescomprise a supply hopper adapted to receive a loose supply of articlesto be counted, a feeder unit for discharging the articles from thehopper, means for advancing the articles one by one to a batchingstation, a detecting unit for sensing each article as it advances to thebatching station, and means responsive to the detecting unit forcounting each article that is sensed. Typically, the means for advancingthe articles to the batching station includes a continuously-movingendless conveyor belt and a guide assembly comprising a pair of guidemembers that define a channel parallel to the belt, sufficient in widthto accommodate the articles in single file. So as to enable one countingmachine to accommodate articles of different shapes and sizes, e.g.,screws, capsules, washers, etc., the guide assembly should be adjustablewith respect to the width of the channel.

In the typical counting system of the type described above, thedetecting unit comprises a light source for producing a beam of lightwhich is disposed so as to be intercepted by the articles carried on theconveyor belt, and a photocell disposed to receive the light beam whenit is not intercepted by an article. The counting means typically is anelectronic or electric counter which counts the number of times thephotocell is deprived of the light beam.

In the machines described in said US. Pat. Nos. Re. 25,0l3 and3,001,636, the detector unit is located downstream of the discharge endof the conveyor and upstream of the batching station, in position todetect articles in their free fall path to the batching station.Experience has demonstrated that such prior counting machines exhibitaccuracy of a high order when counting solid symmetrically-shapedarticles such as tablets, pills, etc. However, it is difficult toachieve the same high degree of accuracy in detecting and counting thin,elongated articles such as nails. In such case the light beam must beaccurately centered with respect to the channel-defining guide membersso that it will be intercepted by each and every article passing fromconveyor to the batching station. In this connection it should beappreciated that the trajectory of the articles depends on their weightand the speed of the conveyor. Hence the position of the light beam mustbe established in accordance with such trajectory. The smaller the crosssection of the articles to be counted, the more critical becomes theneed for properly positioning the light beam with respect to thecenterline of the article channel and the article trajectory. While thedegree of criticality is materially reduced by using two beams displaced90 from one another, it has been found that miscounts can still occur inthe case of objects such as nails which are so small in cross sectionthat they can actually miss both beams. It also has been attempted tosolve this miscount problem by using a wider beam. However this also hasnot been successful since not enough light is blocked to produce aneasily detectable and reliable signal input to the counter.

Accordingly, the principal object of the present invention is to providean article-detecting system that overcomes the above limitations.

More specifically the object of this invention is to provide anarticle-counting machine which is consistent in accuracy, regardless ofthe size and shape of the articles being counted, and which has anarticle-detecting assembly that is easily adjustable so as to insureaccurate detection of the articles being handled.

These and other objects are achieved by providing a photoelectricarticle-detecting unit which is positioned adjacent the upper flight ofthe conveyor belt at the discharge end thereof and which is verticallyadjustable, with respect to the upper flight of the conveyor belt. Thisarticle-detecting unit is embodied in a machine which additionallycomprises a feeder unit, a moving conveyor belt positioned to receivearticles from the feeder unit, a guide assembly that can be adjusted todefine a channel along which the articles are advanced in single file bythe moving belt, a counter responsive to the detecting unit for countingthe articles, and a batching station responsive to the counting meansfor batching the articles in a predetermined number.

Other objects, features and many of the attendant advantages of theinvention are explicitly described or are rendered obvious by thefollowing detailed description which is to be considered together withthe accompanying drawings, wherein:

FIG. l is a perspective schematic view of a particular section of theapparatus of FIG. 2;

FIG. 2 is an elevation side view of a preferred form of article countingapparatus embodying the present invention;

FIG. 3 is a view taken substantially along line 3-3 of FIG. 2, with thearticle-detecting unit removed;

FIG. 4 is a view similar to FIG. 3 but with the article-detecting unitattached;

FIG. 5 is an enlarged, detailed perspective view showing thearticle-detecting unit attached to the article-counting apparatus ofFIG. 2; and

FIG. 6 is an exploded view of the article-detecting unit.

Referring now to FIGS. ll, 2, and 5, there is shown an article-countingmachine which includes a base 20 in the form of a cabinet 22 thatsupports article-handling apparatus comprising a feeder unit 24, a guideassembly 26, a conveying system 28, a detecting unit 30, and a batchingstation 32. The detecting unit and batching station are electricallycoupled to an electric counter 33 which is adapted to count electricalpulses generated in response to articles sensed by the detecting unit 30and to initiate operation of the batching station 32 each time apredetermined count is reached.

A loose supply of articles are discharged into the feeder unit 2%,typically by hand or by a bucket elevator or the like (not shown). Thefeeder unit comprises a conventional bowl 35 with a helical rampextending along the interior surface of its sidewall and adapted toadvance articles in single file to a discharge opening 36 in response tothe influence of a vibrator 33. It is to be understood that the vibratoris adapted to be connected to a suitable power source and that itscontrol circuit embodies a suitable controller (not shown) for varyingits operation so as to modify the rate at which articles are caused tobe discharged from the bowl feeder. Such feeder units are well known inthe art and offer a number of desirable features including reliability,adjustability of feeding rate, and little or no article damage. Thedischarge opening 36 of bowl 35 is located so as to deliver articlesonto the conveying system 23 which generally comprises a frame 39, apair of pulleys HA3, rotatably supported by the frame 39, and a conveyorbelt 4W that is mounted for movement on pulleys 42,43. Although notshown, it is to be understood that the frame 39 also supports a motorand speed reducer and means for transmitting power from the motor viathe speed reducer to the shafts supporting pulleys $2, 33, so that thebelt is driven in the direction by the arrows in FIGS. l and 5, pulley42 is at the discharge end of the conveyor belt.

Associated with the upper run of the belt is the guide assembly 26 whichcomprises two parallel guide members 44,36

(FIG. 3) which cooperate to form a guide channel t7 that serves to alignthe articles on the belt so that they will pass in single file to thebatching station. One of the guide members, preferably member 143, ismovable with respect to the other so as to vary the width of thechannel.

The batching station 32 comprises a hopper 48 provided with a butterflyvalve 50 which is operated by suitable means, such as a rotary solenoidsystem 52. The preferred construction of the hopper is such that whenvalve 50 is one position, e.g., the inclined position of FIG. 1,articles are collected and prevented from passing through the openbottom end 54. Upon actuation of the solenoid system, the butterflyvalve rotates to a second position so as to permit gravity discharge ofarticles onto a delivery chute 56, which may direct the articles tovarious types of apparatus, such as a packaging machine (not shown).Alternatively, the design of valve 50 and hopper 48 may be such that thevalve acts to divert the articles so that they are discharged from oneside or the other of the hopper, with the articles falling through thehopper rather than accumulating therein until a predetermined count isreached. In such an alternate arrangement two chutes 56 would be used,each positioned to receive articles depending upon the position of valve50.

The electric eye system and the rotary solenoid system are connected bysuitable cables 57,58 (FIG. 1) to counter 34 which may be positionedremote from the article counting apparatus (FIG. 1) or mounted withincabinet 22 (FIG. 2). Each time the light beam is intercepted or brokenby an article, a count is registered by the counter. It is to beunderstood that the counter includes a plurality of decade countingcircuits as well as a power supply for such circuits and also fordetecting unit 30 and solenoid system 52. For operator convenience, thecounter may include a plurality of numeric display units 59 one for eachdecade of count. The counter is adapted to count electrical pulsesgenerated in response to articles sensed by the detecting unit 30 andpreferably also includes appropriate control dials 61 which can bepreset to emit an output pulse and initiate operation of solenoid system52 when a predetermined number of counts have been registered. The pulsetransmitted is of sufiicient amplitude and duration to cause thebutterfly valve to reverse its position. The valve then returns to itsoriginal position when another output pulse is received by solenoidsystem 52 from the counter.

As shown in FIGS. 2 and 3, the conveying system 28, detecting unit 30,and batching station 32 are mounted onto a vertical extension 60 ofcabinet 22. This extension includes as an integral part thereof twoparallel side panels 64,66, as well as an end-cover panel 68 (FIG. 3).Overlying the top edge of the side panels and secured thereto is a flattop plate 70 having a laterally extending notch 71 (FIG. located so asto intersect a vertical plane passing through the center axis of pulley42. Also mounted on the extension 60 is a third side panel 72. Panel 72cooperates with panel 66 to enclose the conveyor belt and the pulleys42,43. Affixed to and extending along the top flange of side panel 72 isa flat bar 73 (FIG. 5) having a notch 74 coextensive with notch 71 andalso located so as to intersect a vertical plane passing through thecenter axis of pulley 42. Mounted on bar 73 is guide member 46 which isof triangular or preferably trapezoidal cross section and ischaracterized in having an inclined surface 76 and a shallow guidingedge 78. One end of guide member 46 terminates just short of notch 74.The other end of guide member 46 is located so that it can guide but notinterfere with articles as they leave feeder bowl 35.

The adjustable guide member 44 is made of sheet metal or the like and isformed with a flat, continuous upper surface 80 and a depending sideflange 82 which extends parallel to guide member 46 and is disposedsubstantially perpendicular to belt 40. The lower edge 84 of flange 82terminates close to but short of the conveyor belt. Guide member 44 isfixably secured to a support block 86 by suitable means such as screws87. Block 86 is substantially coextensive in length with top plate 70and is laterally slidable thereon so that guide member 44 can be movedtoward or away from the stationary guide member 46. Since guide member46 is fixed with respect to the discharge opening 36, the onlyadjustment required to be made to achieve proper transfer from the bowlto the conveyor belt in single file is changing the width of the channelby laterally moving support block 86, i.e., moving side flange 82relative to guide member 46. The means for supporting block 86 andsliding it laterally relative to top plate 70 are described in myapplication, Ser. No. 618,497. This same application also describesmeans for maintaining proper alignment of guide channel 47 with respectto the batching station 32.

Referring now to FIGS. 5 and 6, it is shown that the articledetectingunit comprises a light source 88 and a photocell or photodiode 90mounted within yoke assembly 92 which is adjustably coupled to a basemember 94, so as to be vertically adjustable therewith; the base memberbeing fixably secured to the top plate 70. I

Base member 94 is of a regular shape such as a cube or rectanguloid andis characterized by top and bottom surfaces 96,98, ends 100,102, andsides 104,106. Substantially bisecting top surface 96 and extendinghorizontally from side 104 to 106 is a rectangular notch 108 having ahorizontal surface 110. A pair of tapped vertical holes 112 are formedin surface 110. A second rectangular notch 114 bisects the rear side 106and extends vertically from top surface 96 to bottom surface 98. Asshown in FIG. 5, notch 114 is somewhat less in width than notch 108. Avertically elongated through slot 116 extends from substantially thecenter of side 104 to notch 114.

Top surface 96 of the base member is also characterized by a pair ofspaced countersunk holes 118 which extend substantially verticallythrough the base member. These holes are aligned with a correspondingpair of threaded holes 120 fonned in top plate 70 and side panels 64 and66 (FIG. 4). As shown in FIGS. 5 and 6, a pair of screws 122 areinserted into holes 118 and are sized so as to be threadingly engageablewith holes 120, and thus secure base member 94 to top plate 70.

It is also to be noted that a series of graduations are provided alongend surface 102, such as by a rule 124 secured to the base member by anepoxy cement or like means. These graduations may be according to anyconvenient subdivision, e.g., millimeters or sixteenths of an inch, andare arranged so as to indicate the height above the uppermost surface ofbelt 40.

The yoke assembly 92 comprises a pair of matched half-sections 142,144laterally secured to each other by suitable means such as screws 146. Asshown in FIG. 6, the thickness of yoke 92 is such that it is slidablewithin notches 71 and 74. The yoke is formed so that a portion thereofforms a support arm integrally connected to a second portion 152 shapedto define a generally rectangular arch having a pair of opposing legs154,156 the distance between which defines an opening 157 which islarger than the width of conveyor belt 40. The bottom surface of supportarm 150 is flat and coplanar with the bottom surface of legs 154,156.

Although not shown, it is to be noted that the mating sides of the twohalf-sections 142,144 are recessed so as to define any interiorpassageway for one end of cable 58. Sandwiched between the twohalf-sections adjacent the base of leg 156 and disposed toward theopposite leg is photocell or photodiode 90 disposed to receive a beam oflight from light source 88 which is mounted in a correspondingly mannerin the leg 154 adjacent the base thereof. One end of cable 58 isattached to the counter. The other end is coupled to the light sourceand photodiode inside of the yoke assembly 92.

A cubic or rectanguloid block is affixed to the arm position 150 ofhalf-section 142, as by screws (not shown). The size of the block issuch that it makes a closing sliding fit in vertical notch 114. Block170 is characterized in having a vertical tapped through hole 172 and ahorizontal threaded hole 174 which extends into the block and issubstantially perpendicular to yoke 92. Hole 174 is laterally displacedfrom hole 172, as shown in FIG. 6.

The yoke and base member are slidably connected together by a thumbscrew assembly 126 which also permits vertical adjustment of the yoke.Thumbscrew assembly 126 comprises a thumbscrew 130 whose shank includesa large unthreaded section 128 terminating in a threaded section 127that is sized so as to be engageable with hole 1172. Screw 130 isrotatably mounted in a rectangular bracket 1132 having a hole fittedwith a bushing TM. The large unthreaded section 12$ of thumbscrew 130 iscaptivated in bushing 1134 so that the screw can rotate but cannot moveaxially relative to bracket 132. The latter is sized to fit within notch103 and has a pair of spaced through holes 133 which, when the bracketis positioned within the notch, are aligned with tapped holes 112. Thebracket is locked to base member 94 by a pair of screws Mt) which passthrough holes 1138 and mate with tapped holes 112. When the yoke andbase member are connected in the foregoing manner, rotation ofthumbscrew 130 will cause vertical movement of the yoke relative to basemember 94.

Means also are provided for locking the yoke against move ment relativeto the base member. Such means comprises a locking screw 1139 with athreaded shank sized so as to be engageable with hole R74. Screw 190 hasa large head or knob 1184 and is inserted through vertically elongatedslot 116 into hole 174. Because slot M6 is vertically elongated, screw1180 can move with yoke 92 while the latter is being adjustedvertically. While the yoke is adjusted, screw 180 is backed off so thatits knob 1194 does not engage base member 94. After the yoke has beensatisfactorily raised or lowered, screw lltll) is turned until knob MMis tight against surface 10d and the block 170 is drawn up tight againstthe adjacent notch 114 of base member 94, whereupon the yoke and basemember are effectively locked together so as to prevent further verticalmovement of the yoke.

Referring to FIG. 5, it is to be understood that when base member 94l isfastened to top plate 70 by screws 122, the yoke assembly 92 is aligneddirectly above notches 7i and 74. The latter are wide enough to receivethe support arm and legs 1541 and 156 of the yoke and hence permits theyoke to be lowered sufficiently for the light beam to be even with theupper surface of the upper run of the conveyor belt. The actual heightof the beam with respect to the conveyor belt is determined by a line199 which is provided on the leg 154 and functions as a moveable pointerwith respect to scale T24.

Operation of the machine described above is believed to be obvious topersons skilled in the art and is briefly described as follows. Assume asupply of articles of predetermined size are to be counted and batched.The operator first loosens locking screw llbt) just enough to unlock theyoke. Then thumbscrew T39 is turned until the light beam from lightsource 88 is at the desired level above conveyor belt at]. Initially thedesired level is determined by trail and error. Once a satisfactorysetting for the yoke has been achieved the height is noted from scale12d and recorded. Hence when at some subsequent time another supply ofthe same product is to be counted, the yoke height is set using scale1124 as a guide. Assuming that the yoke has been set at the desiredlevel and the machine is operating, articles will be delivered from bowl35 onto the conveyor belt and, because of the channeling function of theguide members Ml and lb, will be transported in single file toward thedetector unit. As each article passes and intercepts the light beam, apulse is generated and transmitted to the counter. Succeeding pulsesgenerated by other articles are similarly received by the counter whichmaintains a total count. After passing the light beam, the articlesshoot off of the conveyor and fall into the batching unit 32 where theyare collected. When a predetermined count has been reached, the counterautomatically produces an output signal that is used to energizesolenoid system 52 and thereby cause the butterfly valve to changepositions discharging the articles to chute 56. Articles continuing tofall into the batcher hopper will be collected until the samepredetermined count is again reached, whereupon the butterfly valve willagain reverse its position and the collected articles will bedischarged. This counting and batching operation continues until thesupply of articles is exhausted or until the vibrator is stopped.

The adjustability of the height of the light beam is advantageous notonly with respect to accommodating different size articles to be countedbut also with respect to conveyor belt thickness. in certain cases whererelatively heavy or abrasive articles are to be handled, it may benecessary to substitute a heavier, i.e., thicker conveyor belt, in whichcase the yoke must be raised if it is desired to maintain apredetermined distance between the light beam and the upper surface ofthe belts upper run. The provision of notches 711 and 7d offer theadvantage that the beam can be lowered so that the bottom portionthereof is just even or slightly below the upper surface of the belt.Having the beam partly obstructed by the belt can be tolerated if theamount obstructed is insufficient to generate a count signal and isadvantageous where relatively thin flat articles are being counted. Anadditional advantage of the invention is that it is not necessary to usetwo intersecting beams to detect the articles being processed. With asingle beam located at the end of the conveyor belt just downstream ofthe two guide members, as herein described, an accurate count ofarticles is easily achieved. Of course, the invention also contemplatesthat the light source and photocell arrangement may be duplicated on thesame yoke so that one or more parallel vertically spaced light beamscross the normal path of the articles.

Since certain changes may be made in the above apparatus withoutdeparting from the scope of the invention herein involved, it isintended that all matter contained in the above description or shown inthe accompanying drawing shall be in terpreted in an illustrative andnot a limiting sense.

I claim:

ll. In combination with an article-counting machine having a conveyingsystem comprising a conveyor belt having an elongated run for carryingsaid articles along a predetermined path to a point at which saidarticles are discharged to a batching station, a feeding unit fordelivering said articles to said conveyor belt, a guide assembly foraligning said articles in single file on said conveyor, said guideassembly terminating short of said point of discharge, and a counterresponsive to a detecting unit arranged to detect said articles on saidconveyor belt, an improved detecting unit connected to said countercomprising:

a light source located to one side of said conveyor belt run betweensaid guide assembly and said point of discharge and oriented so as todirect a beam of light substantially laterally and substantiallyhorizontally over and across said conveyor belt run;

a photocell located at the opposite side of said conveyor belt runbetween said guide assembly and said point of discharge and oriented toreceive said light beam so long as said light beam is uninterrupted byarticles on said conveyor;

support means supporting said light source and said photocell;

means for vertically adjusting said support means so as to adjust theheight of said substantially horizontal beam relative to said conveyorbelt run; and

means for indicating the vertical adjustment of said support meansrelative to said conveyor belt.

2. in combination with an article-counting machine having a conveyingsystem comprising a conveyor belt having an elongated run for carryingsaid articles along a predetermined path to a point at which saidarticles leave said conveyor and are discharged to a batching station; afeeding unit for delivering said articles to said conveyor belt, and acounter responsive to a detecting unit arranged to detect said articleson said conveyor belt; an improved detecting unit connected to saidcounter comprising:

light source located to one side of said run upstream of said point ofdischarge and oriented s as to direct a beam of light substantiallylaterally over and across and substantially parallel to said run;

a photocell located at the opposite side of said run upstream of saidpoint of discharge and oriented to receive said light beam so long assaid light beam is uninterrupted by articles on said conveyor;

support means supporting said light source and said photocell;

means for vertically adjusting said support means so as to adjust theheight of said beam and said photocell relative to said run, whereby theaccuracy of said detecting unit is independent of the trajectoryfollowed by said articles when discharged into said batching station;and

means for indicatingthe vertical adjustment of said support meansrelative to said conveyor belt.

3. In combination with an article-counting machine having a conveyingsystem comprising a conveyor belt having an elongated run for carryingsaid articles along a predetermined path to a batching station, afeeding unit for delivering said articles to said conveyor belt, a guideassembly for aligning said articles in single file on said conveyor anda counter responsive to a detecting unit arranged to detect saidarticles on said conveyor belt, an improved detecting unit connected tosaid counter comprising:

a light source located to one side of said conveyor belt run andoriented so as to direct a beam of light substantially laterally andsubstantially horizontally across said conveyor belt run;

a photocell located along said elongated run at the opposite side ofsaid conveyor belt run and oriented to receive said light beam so longas said light beam is uninterrupted by articles on said conveyor;

vertically adjustable support means supporting said light source andsaid photocell whereby to permit adjustment of the height of saiddetecting unit relative to said conveyor belt run, said support meanscomprising a yoke having a pair of exposed legs and a portion whichconnects said legs and straddles said conveyor belt run, said lightsource supported by one of said legs and said photocell supported by theother of said legs;

a block fixably secured to said yoke and having a vertical,

threaded hole;

a base member fixably secured to said article-counting machine;

a bracket secured to said base member; and

a screw cam'ed by said bracket so that it can rotate but cannot moveaxially relative to said bracket, said screw being engaged with saidvertical, threaded hole so the rotation thereof in one direction willcause said yoke to move vertically upward relative to said base memberand rotation thereof in the opposite direction will cause said yoke tomove vertically downward relative to said base member.

4, The apparatus of claim 11 further including a vertical notch in saidbase member, said notch sized to slidably accommodate said block.

5. The apparatus of claim 11 wherein said block is further characterizedby a horizontal threaded hole and wherein said base member is furthercharacterized by a vertical slot; and further including a threadedlocking screw sized to pass through said vertical slot and be engageablewith said horizontal threaded hole, said locking screw having a knoblarger than the width of said slot so that when said screw is disposedthrough said slot into said vertical hole, said screw can be turneduntil said knob is tight against said slot and said block is drawn upagainst the vertical slot of said support member, whereupon the yoke andbase member are locked together so as to prevent further movement of theyoke.

6. The apparatus of claim 3 further including vernier means formeasuring the vertical movement of said yoke, said means comprising ascale secured on said base member and a horizontal line on the yokewhich functions as a movable pointer with respect to said scale.

7. In combination with an article-counting machine having a conveyingsystem comprising a conveyor belt having an elongated run for carryingsaid articles along a predetermined path to a batching station, afeeding unit for delivering said articles to said conveyor belt, a guideassembly for aligning said articles in single file on said conveyor, anda counter responsive to a detecting unit arranged to detect saidarticles on said conveyor belt, an improved detecting unit connected tosaid counter comprising:

a li ht source located to one side of said conveyor belt run; a potocell located at the opposite side of said conveyor belt run;

, a support member which laterally straddles said conveyor belt run,said light source and photocell mounted to said support member so thatsaid light source produces a substantially horizontal beam of lightwhich passes laterally over and across said conveyor belt and isreceived by said photocell;

a block fixably mounted to one side of said support member, said blockhaving a tapped vertical hole;

a base member fixably mounted to said machine;

a bracket fixably mounted to said base member; and

turning means coupled to said bracket and threadingly engaging saidtapped hole so as to couple said support member and block to said basemember, said turning means when turned in a first direction causing saidyoke to move vertically upward relative to said base member and saidconveyor belt and when turned in a counter direction causing saidsupport member to move vertically downward relative to said base member,whereby the vertical position of said horizontal beam of light isadjustable relative to said conveyor belt run.

UNITED STATES PATENT OFFICE 569 CERTIFICATE OF CORRECTION Patent No. 7,477 Dated April 6 1971 Invntm-(s) Michael C. Klapes It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 7, lines 45 and 49 the numerals "11" are changed to the numerals"3".

Signed and sealed this 13th day of July 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting OfficerCommissioner of Patents

1. In combination with an article-counting machine having a conveyingsystem comprising a conveyor belt having an elongated run for carryingsaid articles along a predetermined path to a point at which saidarticles are discharged to a batching station, a feeding unit fordelivering said articles to said conveyor belt, a guide assembly foraligning said articles in single file on said conveyor, said guideassembly terminating short of said point of discharge, and a counterresponsive to a detecting unit arranged to detect said articles on saidconveyor belt, an improved detecting unit connected to said countercomprising: a light source located to one side of said conveyor belt runbetween said guide assembly and said point of discharge and oriented soas to direct a beam of light substantially laterally and substantiallyhorizontally over and across said conveyor belt run; a photocell locatedat the opposite side of said conveyor belt run between said guideassembly and said point of discharge and oriented to receive said lightbeam so long as said light beam is uninterrupted by articles on saidconveyor; support means supporting said light source and said photocell;means for vertically adjusting said support means so as to adjust theheight of said substantially horizontal beam relative to said conveyorbelt run; and means for indicating the vertical adjustment of saidsupport means relative to said conveyor belt.
 2. In combination with anarticle-counting machine having a conveying system comprising a conveyorbelt having an elongated run for carrying said articles along apredetermined path to a point at which said articles leave said conveyorand are discharged to a batching station; a feeding unit for deliveringsaid articles to said conveyor belt, and a counter responsive to adetecting unit arranged to detect said articles on said conveyor belt;an improved detecting unit connected to said counter comprising: lightsource located to one side of said run upstream of said point ofdischarge and oriented s as to direct a beam of light substantiallylaterally over and across and substantially parallel to said run; aphotocell located at the opposite side of said run upstream of saidpoint of discharge and oriented to receive said light beam so long assaid light beam is uninterrupted by articles on said conveyor; supportmeans supporting said light source and said photocell; means forvertically adjusting said support means so as to adjust the height ofsaid beam and said photocell relative to said run, whereby the accuracyof said detecting unit is independent of the trajectory followed by saidarticles when discharged into said batching station; and means forindicating the vertical adjustment of said support means relative tosaid conveyor belt.
 3. In combination with an article-counting machinehaving a conveying system comprising a conveyor belt having an elongatedrun for carrying said articles along a predetermined path to a batchingstation, a feeding unit for delivering said articles to said conveyorbelt, a guide assembly for aligning said articles in single file on saidconveyor and a counter responsive to a detecting unit arranged to detectsaid articles on said conveyor belt, an improved detecting unitconnected to said counter comprising: a light source located to one sideof said conveyor belt run and oriented so as to direct a beam of lightsubstantially laterally and substantially horizontally across saidconveyor belt run; a photocell located along said elongated run at theopposite side of said conveyor belt run and oriented to receive saidlight beam so long as said light beam is uninterrupted by articles onsaid conveyor; vertically adjustable support meaNs supporting said lightsource and said photocell whereby to permit adjustment of the height ofsaid detecting unit relative to said conveyor belt run, said supportmeans comprising a yoke having a pair of exposed legs and a portionwhich connects said legs and straddles said conveyor belt run, saidlight source supported by one of said legs and said photocell supportedby the other of said legs; a block fixably secured to said yoke andhaving a vertical, threaded hole; a base member fixably secured to saidarticle-counting machine; a bracket secured to said base member; and ascrew carried by said bracket so that it can rotate but cannot moveaxially relative to said bracket, said screw being engaged with saidvertical, threaded hole so the rotation thereof in one direction willcause said yoke to move vertically upward relative to said base memberand rotation thereof in the opposite direction will cause said yoke tomove vertically downward relative to said base member.
 4. The apparatusof claim 11 further including a vertical notch in said base member, saidnotch sized to slidably accommodate said block.
 5. The apparatus ofclaim 11 wherein said block is further characterized by a horizontalthreaded hole and wherein said base member is further characterized by avertical slot; and further including a threaded locking screw sized topass through said vertical slot and be engageable with said horizontalthreaded hole, said locking screw having a knob larger than the width ofsaid slot so that when said screw is disposed through said slot intosaid vertical hole, said screw can be turned until said knob is tightagainst said slot and said block is drawn up against the vertical slotof said support member, whereupon the yoke and base member are lockedtogether so as to prevent further movement of the yoke.
 6. The apparatusof claim 3 further including vernier means for measuring the verticalmovement of said yoke, said means comprising a scale secured on saidbase member and a horizontal line on the yoke which functions as amovable pointer with respect to said scale.
 7. In combination with anarticle-counting machine having a conveying system comprising a conveyorbelt having an elongated run for carrying said articles along apredetermined path to a batching station, a feeding unit for deliveringsaid articles to said conveyor belt, a guide assembly for aligning saidarticles in single file on said conveyor, and a counter responsive to adetecting unit arranged to detect said articles on said conveyor belt,an improved detecting unit connected to said counter comprising: a lightsource located to one side of said conveyor belt run; a photocelllocated at the opposite side of said conveyor belt run; a support memberwhich laterally straddles said conveyor belt run, said light source andphotocell mounted to said support member so that said light sourceproduces a substantially horizontal beam of light which passes laterallyover and across said conveyor belt and is received by said photocell; ablock fixably mounted to one side of said support member, said blockhaving a tapped vertical hole; a base member fixably mounted to saidmachine; a bracket fixably mounted to said base member; and turningmeans coupled to said bracket and threadingly engaging said tapped holeso as to couple said support member and block to said base member, saidturning means when turned in a first direction causing said yoke to movevertically upward relative to said base member and said conveyor beltand when turned in a counterdirection causing said support member tomove vertically downward relative to said base member, whereby thevertical position of said horizontal beam of light is adjustablerelative to said conveyor belt run.